Do you know that this is a gambling section?! In most countries gambling is legal for +18!
Here in my country, there are more adults playing a fish game on arcades than those younger individuals. It might depend on the culture, but arcades here are sometimes more visited by adults rather than children.It's sometimes like in a table pool with a screen, with several players at once. Don't limit an arcade game to a specific age group, some adults do it as their hobbies, how childish the game might look like.
For me if I look at them it's not that childish to look at them playing while gambling because there's no way a kid would understand the game just by looking at the screen without doing something with their hands.
